In the past, it has been known to control fluorescent lamps through the use of electronic ballasts wherein the lamp current was controlled by controlling the operating frequency of the ballast. In such ballasts the lamp voltage was ordinarily uncontrolled. This necessitated different circuits for different wattage lamps in order to avoid over or under powering the lamps.
The present circuit overcomes deficiencies of the prior art by controlling lamp power and provides for easy dimming of fluorescent lamps by matching lamp power to an externally variable reference signal, providing variable lamp brightness.